JP2014109301A - Double row roller bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a double row roller bearing capable of preventing rollers from showing high temperature during use, thereby capable of performing a smooth relative rotational motion between an outer ring and an inner ring.SOLUTION: This double row roller bearing comprises an outer ring formed with at least two outer raceway grooves in a peripheral direction of an inner peripheral surface; an inner ring having at least two inner raceway grooves formed along an outer peripheral surface; rollers arranged in raceways having these outer and inner raceway grooves oppositely formed to each other and having through-holes in a rotating shaft direction; and supplying passages arranged in a radial direction of the outer ring, opened between the adjoining outer raceway grooves for supplying refrigerant between the annular clearances formed between the inner peripheral surface of the outer ring, the outer peripheral surface of the inner ring and roller rows arranged in the raceways. The outer raceway groove and the inner raceway groove are arranged such that the roller raceway surface and the roller guide surface slidably contacted with the end surface of the roller in the rotating shaft direction are crossed to each other, the roller guide surface covers at least a part of the through-hole and then the refrigerant supplied in the annular clearance flows into the through-holes.

Description

  The present invention relates to a double row roller bearing that is used in turning parts of various machine tools and the like, and a roller rolling path is formed in a double row between an inner ring and an outer ring.

  As the double row roller bearing, one disclosed in Patent Document 1 is known. In this double-row roller bearing, two rows of roller rolling paths are formed between the outer ring and the inner ring along the circumferential direction, and a plurality of rollers are arranged on these rolling paths. The roller is configured to revolve while rotating in the rolling path with the relative rotational movement of the inner ring and the outer ring.

  Further, two rolling grooves having a V-shaped cross section are formed on the inner peripheral surface of the outer ring, while two rolling grooves having a V-shaped cross section are also formed on the outer peripheral surface of the inner ring. As a result of facing each other, a pair of rolling paths are formed between the outer ring and the inner ring. By rotating the inner ring and the outer ring relatively, the roller revolves while rotating in the rolling path. The rotation axis of the roller arranged in each rolling path is inclined at an angle of 45 degrees with respect to the rotation axis of the inner ring and the outer ring, and the rotation axis of the roller arranged in one rolling path and the other rolling path The rotation axes of the rollers arranged in the are orthogonal to each other. As a result, this double row roller bearing can be loaded with an axial load acting from a direction parallel to the rotation axis of the inner ring and the outer ring, or a radial load acting from a direction perpendicular to the rotation axis.

  Furthermore, a rolling groove having a substantially V-shaped cross section formed in the outer ring and the inner ring includes a rolling surface on which the roller rolls, and a roller guide surface that faces the end surface in the rotation axis direction of the roller via a minute gap. And intersect with each other at a substantially right angle. Therefore, when each roller rolls on the rolling path between the outer ring and the inner ring, the end surface in the rotation axis direction faces the roller guide surface on the outer ring side, the roller guide surface on the inner ring side via a minute gap, This prevents the roller from tilting (skew) in the rolling path.

JP 05-044720 A

  In the double row roller bearing having the above configuration, the roller rolls along the rolling path in accordance with the relative rotational movement of the inner ring and the outer ring. Therefore, a lubricant is supplied between the outer ring, the roller and the inner ring. Yes. When this double row roller bearing is used while being rotated at high speed, frictional heat is generated between the outer ring, the roller and the inner ring, which causes the outer ring, the inner ring and the roller to be heated. As a result, the temperature of the lubricant also increases, and the lubrication state between the end surface of the roller in the rotation axis direction and the roller guide surface deteriorates, and these frictional forces increase. As a result, there has been a problem that the rolling of the roller in the rolling path, and hence the smooth rotational movement of the outer ring or the inner ring, is hindered.

  The present invention has been made in view of such problems, and its object is to suppress the high temperature of the roller during use, thereby facilitating the relative rotational movement of the outer ring and the inner ring. An object of the present invention is to provide a double row roller bearing that can be used.

  That is, according to the present invention, an outer ring in which at least two outer rolling grooves are formed along the circumferential direction of the inner circumferential surface, and at least two inner rolling grooves facing the outer rolling groove of the outer ring are formed on the outer circumferential surface. An inner ring formed along the outer ring, a plurality of rollers arranged in a rolling path formed so that the outer rolling groove and the inner rolling groove face each other, and adjacent to each other provided along the radial direction of the outer ring A supply passage that opens between the outer rolling grooves and that supplies refrigerant to an inner circumferential surface of the outer ring, an outer circumferential surface of the inner ring, and an annular gap formed by a roller array arranged in the rolling path. ing.

  The outer rolling groove and the inner rolling groove are formed such that the rolling surface on which the roller rolls and the roller guide surface that is in sliding contact with the end surface in the rotation axis direction of the roller intersect. Each roller has a through hole formed along the rotation axis direction. Further, the roller guide surface covers at least a part of the through hole of the roller, and the refrigerant supplied to the annular gap flows into the through hole of the roller.

  According to the present invention, the roller guide surface covers at least a part of the through hole of the roller, and the refrigerant supplied to the annular gap flows into the through hole of the roller. That is, in the present invention, the annular gap and each roller communicate with each other, and the refrigerant is discharged to the outside of the double row roller bearing after flowing into the through hole of the roller. . For this reason, it becomes possible to cool the roller itself rolling in the rolling path, and it is possible to prevent the temperature of the lubricant adhering to the outer ring, the inner ring and the roller from being increased. As a result, it is possible to suppress an increase in the frictional force between both end surfaces of the roller in the rotation axis direction and the roller guide surface, thereby facilitating the relative rotational movement of the outer ring and the inner ring.

It is a perspective view which shows an example of embodiment of the double row roller bearing to which this invention is applied. It is sectional drawing along the rotating shaft direction of the double row roller bearing shown in FIG. It is sectional drawing which shows the detail of the inflow path | route of the refrigerant | coolant with which the double row roller bearing shown in FIG. 1 is provided. It is a schematic diagram which shows the arrangement | positioning relationship between the rotating shaft direction end surface of the said roller, and the said roller guide surface.

    1 and 2 are a perspective view and a sectional view showing an embodiment of a double row roller bearing to which the present invention is applied. This double row roller bearing is composed of an outer ring 1, an inner ring 2, and a number of rollers 3 arranged between the outer ring 1 and the inner ring 2, and the outer ring 1 and the inner ring are rolled by the rolling of the roller 3. 2 are combined so as to be relatively rotatable.

  The outer ring 1 is formed with a bolt mounting hole 10 that passes through the outer ring 1 in the direction of the rotation axis M. A plurality of bolt mounting holes 10 are formed at equal intervals along the circumferential direction of the outer ring 1, and are used when the outer ring 1 is fixed to a base portion of a mechanical device or the like. Further, two outer rolling grooves 11 are formed on the inner peripheral surface 1a of the outer ring 1 with an interval in the direction of the rotation axis M. Each outer rolling groove 11 has a substantially V-shaped cross section. Each outer rolling groove 11 includes a rolling surface 4 on which the roller 3 rolls, and a roller guide surface 5 slidably in contact with an end surface of the roller 3 in the direction of the rotation axis (also referred to as a rotation axis). . The rolling surface 4 and the roller guide surface 5 are inclined 45 degrees with respect to the rotation axis M of the outer ring 1 and intersect each other at an angle of approximately 90 °. The outer ring 1 is provided with a refrigerant supply path 12 inward in the radial direction. The supply path 12 opens between two outer rolling grooves 11 formed in the outer ring 1 in the direction of the rotation axis M. The supply path 12 can be provided at a plurality of locations on the outer ring 1 as necessary.

  On the other hand, a bolt mounting hole 20 is formed in the inner ring 2 so as to penetrate in the rotation axis M direction. In addition, two inner rolling grooves 21 having a substantially V-shaped cross section are formed on the outer peripheral surface 2 a of the inner ring 2 at intervals in the direction of the rotation axis M. These inner rolling grooves 21 are formed on the outer ring 1. The outer rolling grooves 11 are opposed to each other. The inner rolling groove 21 of the inner ring 2 is also constituted by the rolling surface 4 of the roller 3 and the roller guide surface 5 intersecting at an angle of about 90 °. The rolling surface 4 and the roller guide surface 5 are formed by the inner ring. It is inclined 45 degrees with respect to the second rotation axis M.

  The outer rolling groove 11 of the outer ring 1 and the inner rolling groove 21 of the inner ring 2 face each other to form a rolling path on which the roller 3 rolls. Since two outer rolling grooves 11 and two inner rolling grooves 21 are formed in the outer ring 1 and the inner ring 2, two rows of rolling paths are formed between the outer ring 1 and the inner ring 2. . Further, since the outer rolling groove 11 and the inner rolling groove 21 are formed along the circumferential direction of the outer ring 1 and the inner ring 2, each rolling path is formed in an annular shape around the rotation axis M. .

  A plurality of the rollers 3 are arranged in these annular rolling paths, and when the outer ring 1 and the inner ring 2 are relatively rotated, they revolve while rotating in the annular rolling path. Each roller 3 rolls while applying a load between the rolling surface 4 of the outer rolling groove 11 and the rolling surface 4 of the inner rolling groove 21. The rolling roller 3 is in sliding contact with the roller guide surface 5 on the outer ring 1 side and the roller guide surface 5 on the inner ring 2 side at the end surface in the rotation axis direction. Thereby, the skew of the roller 3 during rolling is prevented. Further, each roller 3 has a through hole 32 along the rotation axis direction, and the through hole 32 penetrates both end surfaces of the roller 3 in the rotation axis direction. Further, the rollers 3a arranged in one rolling path and the rollers 3b arranged in the other rolling path have their rotation axes La and Lb orthogonal to each other. The turning center O where the rotation axis La and the rotation axis Lb intersect is provided on the inner side in the radial direction of the inner ring 2, more specifically on the inner side in the radial direction than the outer peripheral surface 2 a of the inner ring 2. The rotation axes of all the rollers 3 arranged in each rolling path are directed to the turning center O.

  According to this configuration, the load acting directions on the rollers 3a and 3b are orthogonal to each other, and the load acting directions on the rollers 3a and 3b are inclined by 45 degrees with respect to the rotation axis M of the outer ring 1 and the inner ring 2. doing. Therefore, in this double row roller bearing, the outer ring 1 or the inner ring 2 can be seen from any direction such as an axial load acting along the rotation axis M of the outer ring 1 and the inner ring 2 and a radial load acting from a direction orthogonal to the rotation axis M. It is comprised so that the load which acts on can be loaded.

  In arranging the rollers 3 on the rolling path, a spacer may be interposed between the rollers 3 adjacent to each other to prevent the rollers from contacting each other.

  FIG. 3 is an enlarged view of a portion A in FIG. A roller support groove 13 is formed on the inner peripheral surface 1 a of the outer ring 1 at a position where the rolling surface 4 and the roller guide surface 5 intersect. The roller support groove 13 is formed continuously along the circumferential direction of the outer ring 1 and faces the end surface 31 of the roller 3 in the rotation axis direction and a part of the outer circumferential surface 33 of the roller 3. A roller support groove 22 is also formed on the outer peripheral surface 2 a of the inner ring 2 at a position where the rolling surface 4 and the roller guide surface 5 intersect. The roller support groove 22 is formed continuously along the circumferential direction of the inner ring 2, and, similar to the roller support groove 13, the end surface 31 in the rotation axis direction of the roller 3 and the outer peripheral surface 33 of the roller 3. Facing the part.

  On the other hand, a predetermined facing gap 6 is provided between the inner peripheral surface 1a of the outer ring 1 and the outer peripheral surface 2a of the inner ring 2 configured as described above (see FIG. 2). The facing gap 6 is open along the direction of the rotation axis M of the outer ring 1 and the inner ring 2, and is formed by an inner peripheral surface 1a of the outer ring 1, an outer peripheral surface 2a of the inner ring 2, and a roller train in each rolling path. It has a gap 61 and a discharge gap 62 partitioned from the injection gap 61 by a roller train in each rolling path. Since each rolling path is formed in an annular shape, the injection gap 61 is formed in an annular shape around the rotation axis M. That is, the injection gap 61 corresponds to the annular gap of the present invention. On the other hand, each discharge gap 62 is formed in an annular shape, like the injection gap 61, and is open toward the outside of the bearing. Each discharge gap 62 is opened along the rotation axis M in opposite directions.

  As described above, the supply path 12 formed in the outer ring 1 opens between the two outer rolling grooves 11. That is, the supply path 12 is opened toward the injection gap 61, and the refrigerant is supplied to the injection gap 61 through the supply path 12. Here, in the double row roller bearing according to the present embodiment, so-called oil air in which a mist-like lubricant and air are mixed is used as a refrigerant, and this refrigerant is supplied to the injection gap 61 by a high-pressure compressor or the like not shown. And supply. A flow path forming groove 24 is formed on the outer peripheral surface 2 a of the inner ring 2 constituting the injection gap 61. On the other hand, the flow path forming groove 24 is continuously formed along the circumferential direction of the inner ring 2, and a first inclined surface 24a that gradually slopes in the direction of the rotation axis M, and the first inclined surface 24a It is comprised from the 2nd inclined surface 24b which inclines in the opposite direction. The first inclined surface 24 a and the second inclined surface 24 b are continuous with each roller guide surface 5 formed on the inner peripheral surface 2 a of the inner ring 2. The first inclined surface 24a and the second inclined surface 24b intersect with each other to form the deepest portion 24c of the flow path forming groove 24. The opening 12a of the supply path 12 is opposed to the deepest part 24c.

  In the slewing bearing of the present embodiment configured as described above, when both end surfaces 31 of the roller 3 in the rotation axis direction are in sliding contact with the roller guide surfaces 5 formed on the outer ring 1 and the inner ring 2, the roller 3 A through-hole 32 formed in the communication hole communicates with the injection gap 61 and the discharge gap 62, and a refrigerant flow path is formed between the injection gap 61, the through-hole 32 and the discharge gap 62. .

  FIG. 4 is a schematic diagram showing an arrangement relationship between the end surface 31 of each roller 3 in the rotation axis direction and the roller guide surface 5. 4 corresponds to an observation of the end surface 31 and the roller guide surface 5 from the direction of arrow B in FIG. In the roller guide surface 5, the width W in the direction perpendicular to the rolling direction C of the roller 3 is set to be smaller than the diameter P of the through hole 32 formed in the roller 3. The guide surface 5 is in sliding contact with the end surface 31 of the roller 3 so that its axis coincides with the axis L connecting the center points Q of the adjacent rollers 3. According to these configurations, in a state where the end surface 31 and the guide surface 5 are in sliding contact with each other, the through hole 32 formed in the roller 3 is not completely covered by the guide surface 5, and a part thereof is the counter gap. 6 is in communication.

  Because of this configuration, the roller support grooves 13 and 22 formed continuously with the guide surface 5 communicate with a through hole 32 formed in the roller 3 as shown in FIG. As described above, since the through hole 32 communicates with the injection gap 61, the roller support grooves 13 and 22 communicate with the injection gap 61 through the through hole 32.

  Such a double-row roller bearing according to the present embodiment can be used in which the outer ring 1 is fixed to the base portion with bolts and the inner ring 2 is rotated relative to the outer ring 1. If the inner ring 2 rotates relative to the outer ring 1, the roller 3 revolves while rotating in the rolling path. In this state, when the refrigerant is injected into the injection gap 61 using the supply path 12, the refrigerant is first injected into the deepest portion 24 c of the flow path forming groove 24. Thereafter, the refrigerant diffuses along the direction of the rotation axis M of the inner ring 2 due to the centrifugal force resulting from the rotation of the inner ring 2 or the revolution of the roller 3.

  Here, the first inclined surface 24 a and the second inclined surface 24 b constituting the flow path forming groove 24 are continuous with the roller guide surface 5, and the through hole 32 formed in the roller 3 communicates with the injection gap 61. ing. For this reason, the refrigerant flows into the through hole 32 along the first inclined surface 24a and the second inclined surface 24b. As described above, since the through hole 32 communicates with the discharge gap 62, the refrigerant that flows into the through hole 32 and flows therethrough flows into the discharge gap 62. Thereafter, the refrigerant is discharged out of the bearing by the centrifugal force resulting from the rotation of the inner ring 2 or the revolution of the roller 3. In this way, the refrigerant flow path is formed by the communication between the injection gap 61, the through hole 32, and the discharge gap 62.

  According to the double row roller bearing according to the present embodiment configured as described above, the refrigerant is discharged outside the bearing after passing through the through hole 32 of the roller 3. It becomes possible to cool the roller 3 itself rolling in the rolling path. As a result, the temperature of the roller 3 can be prevented from being increased, and the temperature of the lubricant adhering to the outer ring 1, the inner ring 2 and the roller 3 can be prevented. As a result, it is possible to suppress an increase in the frictional force between the end surface 31 of the roller 3 in the rotation axis direction and the roller guide surface 5, thereby smoothly rolling the roller 3 in the rolling path, and thus the outer ring and the inner ring. It is possible to facilitate the relative rotational movement of the. In addition, the refrigerant introduced into the facing space 6 from the supply path 12 also flows into between adjacent rollers to prevent the rollers 3 from becoming hot.

  In the double row roller bearing according to the above embodiment, the rotation axis La of the roller 3 a arranged in one rolling path and the rotation axis Lb of the roller 3 b arranged in the other rolling path are the outer circumference of the inner ring 2. The rollers 3 intersect each other on the inner side in the radial direction from the surface 2a, and the rotation axes of all the rollers 3 arranged in each rolling path are directed to the turning center O. That is, the through holes 32 of the rollers 3 are arranged radially with respect to the turning center O. For this reason, it is possible to efficiently guide the refrigerant supplied into the injection gap 61 into the through-hole 32 by utilizing the centrifugal force resulting from the rotation of the inner ring 2 or the revolution of the roller 3. Become. As a result, the roller 3 can be efficiently cooled.

  Furthermore, in the double row roller bearing according to the above embodiment, the flow path forming groove 24 is formed on the outer peripheral surface 2 a of the inner ring 2 so as to face the opening of the supply path 12. And this flow path formation groove | channel 24 is formed from the 1st inclined surface 24a and the 2nd inclined surface 24b which follow the guide surface 5 formed in the said inner ring | wheel 2, These 1st inclined surface 24a and the 2nd inclined surface 24b is gradually inclined in the direction of the rotation axis M. For this reason, when the refrigerant is sprayed into the bearing through the supply path 12, the lubricant in the refrigerant adheres to the flow path forming groove 24. However, the lubricant is efficiently transferred. It becomes possible to supply to the runway and the through hole of the roller 3.

  On the other hand, in the double row roller bearing according to the present embodiment, the roller support groove 13 and the roller support groove 22 communicate with the injection space 61 through the through hole 32 of the roller 3. For this reason, the refrigerant that has flowed into the through hole 32 flows into the roller support groove 13 and the roller support groove 22 by the centrifugal force resulting from the revolution of the roller 3. The roller support groove 13 and the roller support groove 22 face the end surface 31 of the roller 3 in the rotation axis direction and a part of the outer peripheral surface 33 of the roller 3.

  Therefore, it is possible to guide the lubricant in the refrigerant supplied to the rolling path and the through hole of the roller 3 to the roller support groove 13 and the roller support groove 22 by the configuration of the flow path forming groove 24. Therefore, it is possible to lubricate between the end surface 31 and the roller guide surface 5 and between the outer peripheral surface 33 of the roller 3 and the rolling surface 4. As a result, the rolling of the roller 3 in the rolling path can be made smooth. Further, since the lubricant is supplied between the outer peripheral surface 33 and the rolling surface 4 of the roller 3, it is possible to perform lubrication between the adjacent rollers 3.

  In the double-row roller bearing according to the above embodiment, so-called oil air in which a mist-like lubricant and air are mixed is used as the refrigerant. However, it is also possible to use only air as the refrigerant. That is, the refrigerant referred to in the present invention includes only air or oil air in which this air and a lubricant are mixed. When air is used as the coolant, lubrication between the outer ring 1, the inner ring 2 and the roller 3 is performed, and therefore a lubricant such as grease or lubricating oil needs to be sealed between the outer ring 1, the inner ring 3 and the roller 3. . Thus, even if only air is used as the refrigerant, the roller itself can be cooled by the inflow of the refrigerant, and the lubricant adhering to the outer ring 1, the inner ring 2, and the roller 3 is accompanied accordingly. It becomes possible to prevent high temperature.

  In the description of the double row roller bearing according to the above embodiment, the use example in which the outer ring 1 is fixed to the base and the inner ring 2 is rotated relative to the outer ring 1 has been described. It is also possible to rotate the outer ring 1 relative to the inner ring 2 while being fixed to the base portion.

  Furthermore, in the double row roller bearing according to the above embodiment, two rows of rolling paths are formed between the outer ring 1 and the inner ring 2, but the outer ring 1 and the inner ring 2 rotate relatively. If it is the structure which exercise | moves, the said rolling path may be 3 rows or 4 rows, for example.

  Further, in the double row roller bearing according to the above embodiment, the through hole 32 is configured to communicate with the facing gap 6 and the roller support grooves 13 and 22, but the through hole 32 has the injection gap 61 and As long as the refrigerant passage is formed in communication with the discharge gap 62, the through hole 32 may not be in communication with the roller support grooves 13 and 22. However, in performing lubrication between the roller 3 and the roller guide surface 5 and between the roller 3 and the rolling surface 4, the through hole 32 communicates with the roller support grooves 13 and 22, and the through hole 32. It is better to have a configuration in which the injection gap 61 and the roller support grooves 13 and 22 are communicated with each other via a gap.

DESCRIPTION OF SYMBOLS 1 ... Outer ring, 1a ... Inner peripheral surface, 2 ... Inner ring, 2a ... Outer peripheral surface, 3 ... Roller, 4 ... Rolling surface, 5 ... Roller guide surface, 6 ... Opposite space, 11 ... Outer rolling groove, 12 ... Supply 21: inner rolling groove, 32: through hole, 61: injection space (annular gap)

Claims (4)

An outer ring in which at least two outer rolling grooves are formed along the circumferential direction of the inner circumferential surface, and an inner ring in which at least two inner rolling grooves facing the outer rolling grooves of the outer ring are formed along the outer circumferential surface. A plurality of rollers arranged in a rolling path formed such that the outer rolling grooves and the inner rolling grooves face each other, and outer rolling grooves that are provided along the radial direction of the outer ring and are adjacent to each other. A supply path that opens between them and that supplies refrigerant to an inner circumferential surface of the outer ring, an outer circumferential surface of the inner ring, and an annular gap formed by a roller array arranged in the rolling path,
The outer rolling groove and the inner rolling groove are formed so that a rolling surface on which the roller rolls and a roller guide surface that is in sliding contact with an end surface in the rotation axis direction of the roller intersect with each other,
Each roller has a through hole formed along the rotation axis direction,
The roller guide surface covers at least part of the through hole of the roller;
The double row roller bearing, wherein the refrigerant supplied to the annular gap flows into the through hole of the roller. In the outer rolling groove and the inner rolling groove, a roller support groove is formed along the circumferential direction of the outer ring and the inner ring at a position where the rolling surface and the roller guide surface intersect.
2. The double row roller bearing according to claim 1, wherein the roller support groove communicates with the annular gap through a through hole of the roller.   The double-row roller bearing according to claim 2, wherein the rotation shafts of the rollers arranged in each rolling path intersect with each other radially inward from the outer peripheral surface of the inner ring.   A flow path forming groove for guiding the refrigerant supplied from the supply path toward the through hole of the roller is formed on the outer peripheral surface of the inner ring at a position facing the opening of the supply path formed in the outer ring. The double row roller bearing according to claim 3, wherein the double row roller bearing is provided.

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